Carbon nanotubes are becoming increasingly popular in modern electronics — they are more electrically conductive than copper, lighter than plastic, stronger than steel, harder than a diamond and thinner than a human hair. But as production of carbon nanotubes ramps up — currently up to hundreds of tons produced every year — increasing amounts of these tiny structures find themselves in our environment, and nobody really knows what their effects are. Now a new study by Swiss researchers shows that they have measurably harmful effects on good algae found in waterways. These nanotubes reduce the production of algae by causing the organisms to clump together, depriving themselves of light and space.

Previous studies on carbon nanotubes have raised concerns about their effects on human health. One study showed that carbon nanotubes that look like asbestos can cause asbestos related diseases in humans that inhale them. With nanotubes being used in new technologies like solar panels, batteries, medical devices and plastics, they’re becoming increasingly popular and the probability that they will enter our environment is becoming more certain.

The recent study on the effect of carbon nanotubes on rivers and waterways was conducted by researchers from Empa and the Agroscope Reckenholz-Taenikon (ART) Research Station in Switzerland. The team conducted a series of experiments that eventually showed that though carbon nanotubes seem not to have an effect on algae’s photosynthesis, they do cause them to be less productive, stunting their growth by depriving them of light and space. It seems that the effects of carbon nanotubes are just being explored, though these tiny fibers seem to be a perfect solution for conductivity in modern electronics, perhaps they aren’t so great for our health and our environment.